Hydraulic elevator



T. LARSSON.

HYDRAULIC ELBVATOR.

Prmonlox rum JAN. 27, 1903. Hmmm) s521221, 1906.

899,224. Y Patented Sept.22,1908.

2 SHEETS-SHBET 2.

l i@ l0 the following is a specilication. v

'llus invention relates to hydraulic eleva- Ui-'Tlf' ED STATES i f TENTFFICE THURI". LARSSON, OF WGRCESTER. MASSACHUSETTS, ASSIGOR TO HIMSELF,WILLIAM E. D.

STORES, or New vous, r., AND raso A.

JON ES, OF WO KOESTER, MASSACHUSETTS.:

HYDRAULIC ELEVATOR To all whom 'it lmayfoneern: l

De it known that l, Tnenn .Larsson a subject of the iing of Sweden,residing at \\'orcester, in the county of Worcester and State. ofMassachusetts, `have invented new and usei'ul Hydraulic Elevator, ofwhich tors of the direct acting plunger type.

direct acting plunger elevator whic i can he used in high Ihin'ldingsand at high speeds?, with equal or higher eiieiency than otheri typesol' elevators which are now used.

'io these ends, this invention consists of the plunger elevator, and ofthe combinations l of arts therewith as hereinafter described an( moreparticularly pointed out in the` claims a; the end of this syeciiication.

in the accompanying rawings, Figure 1 is a sectionalv view (if sulioientparts of a building to illustrate the application of my inventionthereto, and Fig .2 1s a similar view illustrating a slightly modifiedconstruction.

Theplunger elevator on account of its comparative. simplicity andabsolute safety has ong been recognized as one of the most desirable andprat-tical types of hydraulic eievators for com iaratively short runs ort or use insituations wlhere. high speeds are not desired.

In the largeror taller business blocks, some, of which are, huilt toheights of from two hundred to four hundred feet, it has been thoughtthat the plunger type of elevator could not he used to advantage. lnsome recent instailations, however, plunger elevators have heen employedfor runs of nearly two-hundred and t'vventy-iive feet in length, and ithas heen found that while these elevators can he installed at priceswhich will conipare favorably with elevators which cannot ie operatedwith the same degree of safety, and while these long-run plungerelevators have. been Jfound to operate smoothly and to he readilycontrolled, yet it has been found in practico that the absoluteellioieney of these long-run .lunger elevators does not reach a veryrigh iereentage. This is due to the. fact, that in raising along plungerand a comparatively heavy car, comparatively heavv weights are set inniotion. This, in itself, would notbe found to he objectionable. if itwere possible to Specification of Letters Patent.

Application filed January 27, 1903, Serial No. 140,722.

counter-weight the plunger and car up to the Patented Sept. 22, 1908'.-emma september 21, ma. snaai No. 335,646.

full limit of weight lets the amount of weight required to start tte,unloaded car on its downward travel, which is the limit to which,comparatively short-run low-speed lunger 1 elevators may lie.counter-weight@ Thev i reason why this cannot he done in a long--V irunhigh-speed direct plunger elevator 1s,-

that during the u )ward travel of the eleva- Y tor, the. prepon eranceof the `au.' andV rl he object ot this invention is to rovide a tplunger over the counter-weight must be.

sullieient to overcome the inertia of the ;weig'nted, it would beimpossible to accurately control the upward travel of the rai",-

and in an over counter-weighted system of this kind, the car would.continue itsv up ward travel even after the controlling valve was shut.This .upward jump and uncontrolled motion of the car would draw air downthrough the stuffing box, introducing. an air cushion inside theelevator cylinlder,

and entirely destroying the reliability of op eration. ,Y

ln the high speed plunger elevator plants of over two hundred feet runwhich have ab ready been practically installed it has been foundnecessary to have. a preponderance of weight in the plunger and ear overtheweighhof the counter-weight of nearly thirty-five hundred pounds, andthe ellieieney of suchelevators as heretofore installed has heendecreased hy the amount of power necessarily wasted in4 raising thisunbalanced 'de'ad weight at each stroke of the elevator.

The especial object of this invention is to provide a water circulo tingsystem I or pluriger elevators in which a water column wiilbe' actedupon by the'unbalanced weight o-'tho plunger and the car during the downStroker of the elevator, wherebv a certain amount-ofpressure will bestored fornse. at the next operation, w iichl pressure will assist the,-o eration 'of the supply pump, so that' titi; amount of work to heactually performed the supply pur'np will he diminished, andra. greaterefliciency thus secured, while 'tv'the` same time, the counter-weightwill be ent-i ployed to provide a compensatingbalance. for the greater-part of Athe weight of the pluri-i ger and oar.

e Referring to. -the accompanying drawings for a detail ydescription ofa plungerelevato systemv constructed according to my invention, Figureshows a section of n. building haring its pumping plant. located on oneoi the upper stories. Fig. '.2 shows. u similar construction with thepumping plant. located on the lower lloor or basement..

The dru- ,ings show onl \v sullicient lloers of a building to illustratethe operation ol' the system, it being 1indcrstood f'uit my invention isespecially applicable io long-runs. and

to a considerably greater number of stories than in the buildings heiein illustrated.

is, shown in Fig. l, C designates the eleviitor cylinder which sets intothe ground below the building a. oLstane-e equal to the 5 length of theelevator run. Working up and down inl the cylinder C, :md extendingthrough :i stulliug box in the upper end thereof, is the plunger l),carrying the car A en its upper ond. Connected to the car A are thecounter-weight ropes B, which connect to a count-e -weight W forcounter'- weighting so inucli of the weight of tin "ir A.

` and plunger i as may be possil'e, w iule still leaving the requiredprepondci-mire ol plun- 'y ger and car to stop the upward tran el.

The weights of the cables or counter- "iveight ropes und thecounter-eight ll' are preferably proportioned according to therecognized prictiee which secures the 3o best results in o plungerelevator'. That. is to my, the weight of the cables or counterweightropes B for a given length is mode substitut 'elly e ual to one-half thebuoyancy of n correspon( ing length oi` elevator plunger. Thisdistribution of the weight of ca.- bles or counter-weight ropes providesa coniensuting counter-balance which automat.- ically oil'sets thebuoyancy of the plunger. For example, when the car is near the top of,in its run, as illustrated in Fig. 1, substantially the entire weight.of the counter-right rope B will bey added to thc weight of thecriunter- Weight 'Wg while when the car is near the bottom of its run,and the plunger has displaced -t im equal volume ol' water, and hastherefore its greatest amount. ol' buoyancy tending to raise the sume,the ueight. of the counterweight, rope or cable will oppose the actionof the countcrweight.

Opening into the uppcr end of the c vlindcr .l is a. to-and-l'roin pipe1t) which may bc connccted by tbc valve cit-her with the inlet 'pipe 12or the exhaust pipe l1. 'lluvalve muy be controlled from the carA in anyof .55 the ordinary manners, for example, lu" the standing controllingrope lt.

'lhc parts as thus far described, univ he substantially the same as innn of t li stanil- Y ard plu'hgcr elevator constructions, except 6Utlnit the. inlet and outlet pipesl have heretofore. connected with thesuppl.; nlmp and storugc tank in the basement or lower part of thebuilding, n'liil'e in an apparatus conbuilding for sufiicient distanceto form water' columns to actas hereinafter described. At its upperend,'tl1e outlet pipe 11 is connected with a storage tank T, and thewater l'rfin the storage tenk T is pumped into an nir pressure tank F.

In some cases instead of having two sepa-I rate. witter columns 1'1 und12 for the inletand outlet pipes, and instead of locating the pumpingplant in thc upper part of tho` building. l may emplo)- a single watercolumn 13, as illustrated in Fig. 2, which water column is coniu-rrcd tothe lower part of the storage tank T.

A water column thus located will aid the operation of the. ordinarydouble acting pumps employed in the usual elevator plants in theproportion that the static pressure. of the water eoluuin bears to theworking pressure, refpiired for the elevator. That is to sur, in unordinarydouble-acting force pump, both sides of the pump iston are inContact with the. water, and if t 'ie water is admitted under pressure'to the pump cylinder, this pressure acting on the hack or inoperativeside of the piston will aid in moving the piston on its working stroke.to locate. the pumping plant und the pressure tank in the u )per partofthe building, beenlise. when located in this position, theI pump and thepressure tank ill operate only under such additional pressure as must beadded to the water column in the supply pipe 12 to make the pressurerequired to operate the'eltw'ator, while in thc construction shown inFig. 2, the pump and pressure tank arc required to withstand the l'ullworking pressure required in the elevator cylinder.

In the construction shown in Fig. 1, the inletl pipe l2 forms in ell'ecta. continuation of the pressure tank l*` and lor this reason, theconstruction illustrated in Fie. 1 will permit thc use of a somewhatsmaller pressure tunk than will the construction illustrated in Fig.2.

ln the operation ol' u plunger elevator constructed according to myinvention, tlu` necessar)v piepontlcrancc of plunger and cur over thecounter-weight will operate. during the down stroke ol the elevator toraise. a wu.- ter-coluxnn, lifting a cer'tnin amount. of water to theelevated storage tank which will give. n f eztain static hcad orpressure of water, which will diminish the amount of work rcquircd to bedone b v the suppl) um i. For example, in a tuo-lunulred and hltylootrun elevator laut here the required preponderance ol` tlie car andplunger over the counter weight is approximately thirty-live hundredpounds, a plunger' six and one-hull` inches in diameter will requiret\\'oliuiulred pounds working pressure to secure the desired speed olopyiution.

lu direct henger elevator svstcnis as herestructed according to myinvention, the inlet tolore insta led, this entire workin-, pressure undoutlet pipes 11 and l2 extend up into thc l ol' two-hundred pounds isfurnished entirely 13o l prefer, however,

too

l i l by the suppl)Y pump, wllilo in an :apparat-us constructed nur:orrling lo my inv tition, more than half the working pressure- '.fillbe supplied by the walor uoiuinu.

.l a-:n aware. ibut runny dill'crunl mer-cirulalng systems luive beendevised for opcr- 1 ating elevator plants, and flint w. tr-r uns beenexhausted from olvvator constrummns in u minibar ol' rlillbrcn ways,:unl u ecrl for different purposes, und my invention iloos notJ folateto .auch systems lxrozully, tlm cspoi cia-l object of my invvnion livinglo couilnuo a direct plunger elei'utor.\\titli u unter-gol uinn for1re-Willing the. requisito prupomivl-` ance of elevator und plungur owrLlic counter-weight from resulting in loss of vilicicncy.

l :un also aware that changes may lle made 1n applying luy invention tohydraulic elevalors.

l lo not wish, tluircl'orri, lo lm lizuivrl to 5' tlu. construction lhave herein shown :unl rluscrilu-rl, buty Wluit l glo vlailn and desireto Secure by Letti-rs Patent of tlm Unitvrl States 1s.-

1. In :xliydrzxulic elevator system, the: coinlnnatlon of zi. verticalcylinder, a plunger running insnirl ('ylimlvr, a wir on tlm upper curlof the plunger, n countcriznianu'c for tlu: grratcr part of tlm weightplt alle rar und plunger willi tlic counter-weight nulles uct-- l Ing tooll'set the buoyancy of tlnl plunger, :l .to-nnd-l'ronx pipo openinginto tlu: upper und of the cyliiulvr, u storage luuk conucctvrl theretoand lor-:uml fur fnougll :lliure ille upper 0nd ol' thu. cylinnlvr soilnu its simic pressure will substantially lullzmmllw preponrluruncc inu'vijgli oi' plungvx' nml zur over tlwir voulu r-lml:rnru prvssun' inni,null :l pump inlormmlizuu illu :lola-ugo luuk :unl

:muy ol` llw plunger, :L 'lo-:uul-l'rom pip wnnvutml to line upper vuilof {luv}luulr-r. :zu elevated sloragcbink, un outlm pipf loadingl-licrr'lo, :l prusorv huil". :1 pump inlvrnwflil :ite Lluprvssurrh luuk:unl torngiv tank, :in

